The present invention relates generally to tube forming machines and methods and, more particularly, to a tube forming machine and method in which a flat workpiece is shaped into a cylindrical tube.
Prior art tube forming machines and methods are known which utilize a continuous belt which wraps partially around a cylindrical mandrel. As the mandrel rotates, a workpiece is fed between the belt and the mandrel to shape the workpiece. Machines and methods of this type are shown in U.S. Pat. Nos. 608,706, 2,990,001, and 3,357,222.
Tube forming machines and methods are also known which include a cylindrical mandrel and two back-up rolls which wrap a flat workpiece around the mandrel. After the flat workpiece is deformed, one end of the mandrel is released to permit removal of the workpiece. Machines and methods of this type are disclosed in U.S. Pat. Nos. 1,590,491, 1,973,164, and 2,432,666.